Does the potentiometer connect to the small knob protruding from the gauges? If so there is a good chance that the plug into the potentiometer has come off during work on the dash. Or the potentiometer has failed. The latter seems unlikely. On second thought if the potentiometer is not solid state it could have corrosion. The gear selection light does not work either. However, they could have separate problems. Thanks for you help.
1988 560SEL, Green, Chrome wheels.
2000 Suburban, 20" wheels, DVD, wood grain dash (wife's car).
67 Beetle euro, Lots of Empi parts.
69 Beetle conv, 1980s cal look.